牛精子蛋白激酶C抑制剂逆转KB/VCR的作用及其机理

Role and Mechanism of PKC Inhibitor from Bovine Spermatozoa in Reversal of MDR in KB/VCR

目的 :研究牛精子蛋白激酶C抑制剂 (PKCI)对肿瘤细胞多药耐药性的逆转作用及机理。方法 :选用KB细胞及其耐长春新碱的耐药株 (KB VCR)测定其蛋白激酶C活性及PKCI的影响 ,用MTT法测药敏 ,用流式细胞仪测定细胞对罗丹明 1 2 3的蓄积及外排。结果 :耐药细胞细胞膜的蛋白激酶C活性是亲本细胞的 2 9倍 ,耐药性是亲本细胞的 1 72倍。经PKCI作用后 ,罗丹明 1 2 3的蓄积量增加了 6 8倍 ,外排明显延缓 ,外排后潴留增加了 4 3倍 ,耐药性被逆转了 1 0倍。PKCI对亲本株的蛋白激酶C活性和耐药性影响不大。结论 :PKCI可明显地逆转耐药细胞的多药耐药性 。

Objective To identify the role and mechanism of PKC inhibitor from bovine spermatozoa (PKCI) in reversal of multidrug resistance in KB/VCR.Methods PKC activity and the effect of PKCI were assayed by using KB cell and vincristineresistance cell(KB/VCR).Drug sensitivity was assayed by using MTT method,and intracellular accumulation and efflux of rhodamine 123 were assayed by using flow cytometer.Results PKC basic activity was 2 9 fold higher and the resistance to vincristine was 172 fold higher in KB/VCR compared with that of KB cell.After treatment with PKCI,the accumulation and efflux of rhodamine 123 increased by 6 8 fold and slowed down respectively,post efflux storage increased by 4 3 fold,and drug resistance was reversed by 10 fold in KB/VCR,while PKCI had little effect on KB cell.Conclusions PKCI could apparently reverse MDR in KB/VCR,whose effect was a little bit stronger than relative specific PKC inhibitor H7.